.icon-user {
    background-image: url(images/restful/user.png) !important;
}

.icon-add {
    background-image: url(images/restful/add.png) !important;
}

.icon-delete {
    background-image: url(images/restful/delete.png) !important;
}
.icon-refresh {
    background-image: url(images/restful/user.png) !important;
}